(a) Field of the Invention
The present invention relates to a microscope objective lens system and more particularly to an achromatic microscope objective lens system having a flat field.
(b) Description of the Prior Art
In a conventional microscope objective lens system of this type, although an image plane was flat, it was not sufficiently flat to the surrounding area of the visual field and only in the vicinity of the central portion was there a flat image plane. Further, when the image plane was flat over a comparatively large area, the numerical aperture was small.